Now, Zelenskyy, who was once a TV comedian, is facing off against Putin's army.

Three years ago, he acted as a president in a well-known TV comedy. Now, he is the president of Ukraine, facing Russia's powerful military forces.

The ongoing conflict in Ukraine, which is being led by Volodymyr Zelenskyy, has the potential to escalate into the most severe post-World War II conflict in Europe.

On Friday, Russian troops arrived in Kyiv, and he posted a defiant video on social media, standing next to the presidential palace in the center of the Ukrainian capital, surrounded by members of his Cabinet.

"We are defending our independence and country," he stated.

Who is the man leading Ukraine through its most significant challenges, having previously made jokes on television?

In 2019, Zelenskyy, a 44-year-old lawyer, became president and discovered his true passion as an entertainer.

He was born in Kryvyi Rih, in the Soviet Union, to Jewish parents and is married to Olena Zelenska, with whom he has two children.

His family's history mirrors the continent's and his homeland's bloody past, as he recounts the story of three of his grandfather's brothers being killed by Nazi occupiers, while his grandfather survived WWII.

Zelenskyy, who was raised during communism, entered politics months before the 2019 election with no prior experience or solid policies. However, he campaigned on a promise to restore integrity in his country's leadership.

Unlike many politicians in his region, he did not become bitter and cynical due to his past. Instead, his public image is defined by one of his most famous sayings: "Being president doesn't require experience, it requires being a good person."

He is recognized for his friendly demeanor and his talent to connect with diverse audiences as a result of his background in the entertainment sector.

Orysia Lutsevych, a research fellow at Chatham House, stated that he is successful in politics due to his empathetic nature and ability to form good connections with people.

Zelenskyy, a native Russian speaker, won a landslide victory in Ukraine's presidential election with his charisma and immense popularity. He was supported by voters in the country's south and east, where millions of Russian-speaking Ukrainians felt disenfranchised by previous administrations. This alienation is what Russia has tried to capitalize on by supporting separatists who have been fighting Ukrainian forces for eight years.

Not the first time Zelenskyy has been thrust into the spotlight, this week's invasion of Ukraine by Russia, which followed months of Russia massing troops on Ukraine's borders and demands from President Putin that NATO prevent Ukraine from joining the military alliance, has brought him into the global limelight.

A phone conversation between Trump and Biden, in which Trump urged Biden to investigate corruption allegations against him, drew international attention. This scandal ultimately led to Trump's first impeachment, which he was acquitted of in early 2020.

Lutsevych stated that Zelenskyy had already disrupted the Ukrainian political system by bringing in individuals who desired to modernize the country.

Despite his efforts to curb corruption and challenge the established power structures in Ukraine, he was unable to gain enough political influence to effectively address the deeply entrenched corruption within the system, as she pointed out.

While he has been commended by numerous individuals in Ukraine for maintaining the country's course towards the West, Russia and Ukraine have grown increasingly distant from each other since the dissolution of the Soviet Union in 1991, with Kyiv striving for greater ties with Europe.

In 2014, Viktor Yanukovych, a pro-Kremlin president, was ousted from power due to his refusal to sign an association agreement with the European Union.

The accusation that Zelenskyy is a Western "marionette" by Russian officials has been fueled by the fact that Ukraine is a democracy, which is perceived as a threat to the Kremlin. Propagandists from the Kremlin often mock Zelenskyy, claiming that he is incompetent.

Zelenskyy has been criticized for not fulfilling his promise to end the conflict between government forces and separatists in eastern Ukraine, which has resulted in the deaths of 14,000 people. The conflict escalated last week when Russia recognized the independence of the Donetsk and Luhansk People's Republics, leading to an invasion.

In the face of rising tensions before the invasion of Ukraine, Zelenskyy played down dire warnings from Washington that Moscow was planning to attack, claiming it would harm Ukraine's already fragile economy and morale.

Earlier this month, he spooked the markets and sent the foreign media into a frenzy when, in his typically sarcastic style, he appeared to say in a speech that Russia would attack on Feb. 16. However, he later clarified that he was only referring to media reports of an invasion on this date.

American late night show hosts joked about his calm tone, which they found too relaxed, causing many to question it.

Last week, it became clear that Ukraine was running out of diplomatic options to appease Putin. Despite Zelenskyy's efforts to maintain calm, he adopted a more serious tone and emphasized Ukraine's readiness for any threat while advocating for peace.

In the lead-up to the invasion and as commander in chief, Zelenskyy has transformed into a wartime leader, and Ukrainian society, including his peacetime opponents, are currently supporting him, according to Kyiv-based political analyst Valentyn Gladkykh, who spoke to NBC News.

Zelenskyy has demonstrated his best side by dealing with an unprecedented threat, which is a full-on invasion on his territory.

Despite his best efforts, Ukraine faces a formidable opponent in Russia, which is much larger and better equipped.

The difference between Zelenskyy and his counterpart in the Kremlin became increasingly stark within hours of Russia's first strikes.

Putin, in his stern ex-KGB officer tone, spoke in his address to justify an incursion into Ukraine late Wednesday, invoking Russia's nuclear arsenal and warning anyone who tries to stop him.

"Anyone who doubts that attacking our country will result in defeat and severe consequences for the aggressor should have no doubts," he stated.

Zelenskyy, visibly exhausted, made a last-minute plea for peace in Russian, appealing directly to Russian citizens.

He warned about the devastation that the war would bring to both people, stating that the people of Ukraine desire peace.

If Russian leaders refuse to negotiate with us for peace, perhaps they will negotiate with you," Zelenskyy implored. "Do Russians desire war? I would like to know. However, the answer lies solely with you.

As Putin's bombs rained down on Ukrainian soil, Zelenskyy implored Russians to stand against the war. He thanked those who spoke out against it on Friday, saying, "Keep fighting for us."

There is speculation that Putin's goal in Ukraine is to remove Zelenskyy and install a president who will be more compliant with Moscow. Last month, Britain stated that the Kremlin is seeking to install a pro-Russian leader in Ukraine as part of its plans for an invasion.

Zelenskyy stated on Thursday that Russia aims to politically destroy Ukraine by targeting its president, himself, but he pledged to remain in Kiev.

On Friday, Putin urged Ukrainian soldiers to overthrow their government, while suggesting he might be open to negotiations, as his forces continued their advance across the country.

As the Russian offensive intensifies, Zelenskyy is left with limited options. He could surrender to Moscow, which may not be well-received by many Ukrainians, or maintain his stance and confront the full force of the Russian military.

For now, he remains defiant.

In the video posted on Friday, he stated, "It will continue like this." He added, "Glory to our defenders, glory to Ukraine."